Explanation of an open relay;



When you connect to your server to send Email using your Internet Email server (this is called an SMTP server) you are usually authenticated. This is done in one of two ways. The first way is that the server checks your IP address (how you are found on the internet) to make sure it is one that was assigned to you by the same company that is providing the server. The second method is by prompting you for a user name and password (this is usually saved when you setup your Email software so that you are not prompted for it each time). This prevents anyone who shouldn’t from connecting to the server to send Email and provides some accountability for Email that is sent. If this was not done then anyone on the Internet could use the server to send any sort of Email (spam for example) and not be held responsible. Thus only authenticated and trusted senders are allowed to use, or relay from, the server. An unsecured server will usually become the source of uncontrolled spam within a few days, often sending millions or even billions of spam Emails in a single day. This type of unsecured server is called an open relay. It is standard practice for most companies to reject Email from a server that is an open relay.